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The current study sought to address the utility of the Rey Fifteen Item Test (Rey-15), with the use of a combined score [recall correct + (recognition correct – false positives)], to distinguish between valid and invalid performance among a sample of litigating persons referred for neuropsychological evaluation. Scores on the Rey-15 were analyzed across four comparison groups: (1) litigating persons with evidence of invalid performance (n = 29), (2) litigating persons with valid performance (n = 63), (3) learning-disabled patients (n = 36), and (4) a mixed clinical neuropsychological sample not involved in litigation (n = 54). A Rey-15 combined cutoff score of < 21 yielded the highest sensitivity (70%) and specificity (92.8%) rates. If the Rey-15 is to be used in clinical practice to detect invalid performance, the recognition trial with combined score < 21 should be used. Findings support the use of the combined Rey-15 score in place of the previously used recall Rey-15 score to improve sensitivity and specificity rates for detection of invalid performance in litigating neuropsychological referrals.  相似文献   
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BackgroundPulmonary hypertension (PHT) and right ventricular (RV) dysfunction are among the commonly observed and potentially serious complications following heart transplantation. RV dysfunction is reported to occur in as much as half of these patients. In this study, the authors sought to examine the prevalence and the course of these prognostically important complications.MethodsThe records of 30 patients who had undergone orthotopic heart transplantation at our center were examined. Demographic and clinical variables were noted; RV dysfunction, pulmonary artery pressure on Doppler echocardiographic examination, and catheter findings were recorded.ResultsThe mean age of the study population was 31.3 years. On preoperative assessment, PHT was present in 21 (70%) patients. The average value of systolic pulmonary artery pressure was 44.5 ± 5.9 mm Hg. The mean value of pulmonary vascular resistance was 3.3 ± 1.8 hybrid reference unit (HRU). RV dysfunction was detected on postoperative assessment in 17 (56.7%) patients. The mean ischemia time was 216 ± 77 minutes; in 3 cases it exceeded 5 hours but in none of the cases did it reach 6 hours. Rejection was detected in 14 (46.7%) patients. Most of the patients received inotropic agents in the early postoperative period. When compared with preoperative values, on follow up at the end of the first year, a significant decrease in pulmonary artery pressure was observed (47.4 ± 4.8 vs 38.5 ± 7.5 mm Hg; P = .03), and the ratio of patients experiencing RV dysfunction decreased to 16.6% (n = 5).ConclusionThe findings of this study indicate that RV dysfunction and PHT are common complications following heart transplantation and improve with appropriate management over time with monitoring.  相似文献   
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The purpose of this study was to evaluate the influence of different surface treatments (sandblasting, acid etching, and laser irradiation) on the shear bond strength of lithium disilicate-based core (IPS Empress 2) and feldspathic ceramics (VITA VM 9). One hundred ceramic discs were divided into two groups of 50 discs each for two ceramic systems: IPS Empress 2 (group I) and VITA VM 9 (group II). Each of the two groups was further divided into five surface treatment groups (ten each) as follows: group SB, sandblasting with alumina particles (50 μm); group HF, 5 % hydrofluoric acid etching; group L, Er:YAG laser irradiation (distance, 1 mm; 500 mJ; 20 Hz; 10 W; manually, noncontact R14 handpiece); group SB–L, sandblasting + Er:YAG laser; and group HF–L, 5 % hydrofluoric acid + Er:YAG laser. Luting cement (Panavia 2.0) was bonded to the ceramic specimens using Teflon tubes. After 24 h of water storage, a shear bond strength test was performed using a universal testing machine at a crosshead speed of 0.5 mm/min. The data were analyzed with a two-way analysis of variance (ANOVA) and Tukey's honestly significant difference tests (α?=?0.05). The two-way ANOVA indicated that the shear bond strength was significantly affected by the surface treatment methods (p?<?0.05), but there was no significant interaction between the ceramic systems. Group SB–L had the highest mean values for each ceramic system. Sandblasting, followed by Er:YAG laser irradiation, enhanced the bond strength, indicating its potential use as an alternative method. The atomic force microscopic evaluation revealed that group SB had the most distinct sharp peaks among the groups.  相似文献   
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The use of large diameter metal bearing total hip arthroplasty (THA) and hip resurfacing arthroplasty (HRA) increased in popularity in the last decade. More recent literature has highlighted the effect of head size in patient outcomes. Data was obtained from the Australian Orthopaedic Association National Joint Replacement Registry (AOA-NJRR) to evaluate the Birmingham (MoM) bearing surface when used with THA and HRA. There is no difference in the overall rate of revision between the THA and HRA but head size has a significant effect on revision rate. The data show that small diameter metal bearings in HRA (below 50 mm) have a higher rate of revision than large diameter metal bearings in HRA (equal to and above 50 mm) (P < .001). Conversely the large diameter metal bearings in THA have a higher rate of revision than the small diameter metal bearings in THA (P = .027). The revision rate for large diameter HRA compared to small diameter THA is not significantly different P = .670. We recommend caution when choosing either a large diameter (≥ 50 mm) metal on metal THA or small diameter (< 50 mm) HRA.  相似文献   
80.
The standard Exeter stem has a length of 150 mm with offsets 37.5 to 56 mm. Shorter stems of lengths 95, 115 and 125 mm with offsets 35.5 mm or less are available for patients with smaller femurs. Concern has been raised regarding the behavior of the smaller implants. This paper analyzed data from the Australian Orthopaedic Association National Joint Replacement Registry comparing survivorship of stems of offset 35.5 mm or less with the standard stems of 37.5 mm offset or greater. At 7 years, there was no significant difference in the cumulative percent revision rate in the short stems (3.4%, 95% CI 2.4-4.8%) compared with the standard length stems (3.5%, 95% CI 3.3-3.8%) despite its use in a greater proportion of potentially more difficult developmental dysplasia of the hip cases.  相似文献   
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